Effect of Material Behaviour on Flow Uniformity over Different Spillway Weir Profiles

J Dilip Singh,Lijalem Mulugeta,G Senthilkumar,V Vijayan

doi:10.1155/2022/8774617

Abstract

The spillway weir system finds an important application to achieve uniform flow in the open canal stream passages, for irrigation and in many industrial processes, majorly including cooling of reactor components with liquid sodium in prototype fast breeder reactors, process plants, and power industries. The optimal design of weir profile and the velocity of flow over the weir are the critical factors that need to be optimized to minimize flow separation in order to avoid entrainment of gas in flowing liquid, and also, the nonuniform cooling resulted in uneven temperature distributions in many thermohydraulic structures. In this research, the spillway weir profile made from SS-316, SS-304, concrete, and teak wood is compared for optimization of flow uniformity by means of hydraulic experiments conducted on the water-air model and also to investigate the behavior of flow past over the rectangular weir of three different radii 6 mm, 6.47 mm, and 7 mm, respectively, and the minimum of 1.2% flow separation was observed with 6.74 mm profile, and also, the computational fluid dynamics (CFD) based numerical simulation was performed in the fluid domain to validate the experimental data to attain the flow uniformity when flow past over the spillway weir profile and the results are highlighted. The experimental results on air entrapment, water film thickness, and velocity of water over the weir profile on the perspective of uniformity of flow are also discussed in detail.

Highlights

In an open water way flow passages and in many chemical processing units, the supposition is that the spillway system paves way to water flow with uniformity for which it is essential to consider the passage length as a function of flow rate. e fascinating idea in the spillway is the profiling of the weir crest
The profile optimization is the basis of the spillway design for ensuring the flow uniformity, and focus is needed for minimum thickness, height, and the inward bend of the weir for cost-effectiveness without sacrificing the safe design of weir profile
The water film thickness has to be measured at various points on the downstream side to identify the impact velocity, which has strong concern on air entrapment. e experimental results for the effect of spillway profile on the air entrapment study are highlighted. e water film thickness and the drag coefficient are the measured physical quantities

Summary

Introduction

In an open water way flow passages and in many chemical processing units, the supposition is that the spillway system paves way to water flow with uniformity for which it is essential to consider the passage length as a function of flow rate. e fascinating idea in the spillway is the profiling of the weir crest. E experiment on the spillway weir optimization for minimization of entrainment of air and bulk air bubbles in water at different fall heights of water over the weir profile on the downstream side of flow passage was analyzed. An ultrasonic sensor was used to measure the thickness of water over the weir In this experimental model, water is used as working fluid at room temperature (i.e., 303 K) and enters into the upstream through a single inlet pipe of entry diameter 80 m to overflow the weir and to the downstream by gravity. Result and Discussion is section describes the experimental results on air entrapment and water film thickness and the validation of flow pattern with CFD simulation as follows

20 Detail B Scale: 2:15 Figure 3

ASSEMBLY

Findings

Disclosure